Every thinker, as Heidegger used to say, follows the line of a single thought. What he forgot to mention was that no thought belongs to a single thinker. Ideas are not born from the depths of a self-enclosed mind. They always come from somewhere else, from a place ‘out there’: an intellectual tradition, an academic teacher, a school of thought, a social movement, an academic or non-academic discussion, a reading that turned out decisive, or simply an inspirational moment in a conversation. Intellectual work, rather than being a solitary endeavour, is a collaborative one. If there is originality in intellectual work, it is originality without determinable origin. For this reason, ideas are never the property of an individual. It is impossible to ‘own’ an idea – which is but an ideological fantasy rooted in the capitalist system of property ownership. Ideas can only be disowned – in a movement described in this book as one of selfimplication – as they emerge from, and return to, an a-subjective, collective effort that cuts across temporal and geographical barriers. One of these ideas bears the name ‘antagonism’.

This concept, which rings the bell of conflictuality but is not equivalent to conventional notions of ‘conflict’, ‘struggle’ or ‘war’, has an extended history. Antagonism is the name that was given to the phenomenon of social negativity in the tradition of German Idealism, Early Romanticism and Marxism. It was carried forward by the Heideggerian Hegelians of the first half of the twentieth century, among them Kojève, Sartre and Lacan. This concept was born from a collective inquiry that reaches back more than two hundred years, but it was in the work of Ernesto Laclau, initially in his path-breaking book Hegemony and Socialist Strategy (HSS), co-written with Chantal Mouffe, that ‘antagonism’ found a contemporary systematic treatment. When the book appeared in 1985, it was immediately realised by Slavoj Žižek that this conception constitutes ‘the most radical breakthrough in modern social theory’ (Žižek 1990: 249).

Laclau, who passed away in April 2014, was one of the major theoretical voices on the Left. Born into a radical-liberal family in Buenos Aires in 1935, Laclau turned to Peronism as a university student.